Device for opening crimped continuous tow for cigarette filters



Filed April 2, 1964 y 1967 SHlGEl-HKO mcrczw 3321 30 DEVICE FOR OIENING CRIMPED CONTINUOUS TOW FOB CIGARETTE FILTERS 2 beets-Sheet 1 IN VENTOR shig hiki) Karla ATTORNEYS y 1967 SHIGEHIKO KATO 3321,3@$

DEVICE FOR OPENING CRIMPED CONTINUOUS TOW FOR CIGARETTE FILTERS Filed April 2, 1964 2 Sheets-Sheet 2 United States Patent Japan Filed Apr. 2, 1964, Ser. No. 356,865 Claims priority, application Japan, Apr. 10, 1963, 38/17,623 3 Claims. (Cl. 19-65) The present invention relates to a device for opening the filament tow necessary in the manufacture of cigarette filters from continuous crimped filament tow characterized in that it is so constructed that a continuous crimped filament tow is passed between the upper and lower belts to which needles are secured, the speed of said two pairs of belts being intermittently changed and opening the gap between belts at the outlet of said belts to complete the filament opening operation.

In order to uniformly pass the smoke through a cigarette filter it is desirable that the filament tow to be used for the filter should be bulky and there is no accumulation due to the cohesion of filaments. As the method which has heretofore been commonly used for making such well openable cigarette filter filament tow there are roller processes wherein two pairs of rollers are provided and by changing their speeds the tense portion and slack portion are given to filaments and when these filaments are recovered to the normal condition each of filaments is subjected to the crosswise force to swell up the filament, and an air blowing process for blowing compressed air to open the filaments and the high speed vibration process for giving violent reciprocating motion in a direction normal to the filament between two pairs of rollers. The roller process has disadvantage that small bundle of filaments remains not open and in the air blowing process and high speed vibration process there is tendency of causing deviation and also reducing crimps of filaments so that they are not sufficiently satisfactory as the device for opening the filaments for cigarette filters.

According to the invention provision is made of upper and lower belts which have needles secured to the surface and means for driving these belts intermittently and at unequal relative speeds such that one belt runs at a higher speed than the other belt and stops while the other belt continues to run, whereby needles on the belt fixed in the comb-like state stick into the filament tow and positively hold the filament tow to give continuously the tense and slack condition alternately and moreover, the gap between the upper and lower belts is widened toward the outlet opening to give bulkiness to the filament tow and the object of sufiiciently opening the filaments can be attained at a difference in belt speeds at less than the crimping and shrinkage degree without liability of losing crimped state.

For a better understanding of the invention reference is taken to the accompanying drawings, in which,

FIG. 1 is a diagrammatic side view of the opening mechanism of the device embodying the invention;

FIG. 2 is a partial sectional view of the needle belt to be used for the device of the invention;

FIG. 3 is a partial side view illustrating of needle portion of the needle belt;

FIGURE 4 is a side view of a Geneva mechanism used in the device according to the invention; and

FIGURE 5 is a partial sectional view of the back roll taken along the line A-A' of FIGURE 1.

The mechanism for opening the filament of the device of the invention, as shown in FIG. 1, comprises needle belts 1 and 2, back rollers 3 and 4, intermediate rollers an example 5 and 6, front rollers 7 and 8 and control rollers 9 and 10 arranged substantially symmetrically one upon the other and the two Geneva mechanisms for operating the upper and lower belts'intermittently. Each of these mechanisms comprise a pin wheel 12 having two pins arranged in symmetrically opposite positions and a slotted wheel identified as numerals I1 and 11 in FIGURE 5. The slotted wheel 11 of one Geneva mechanism is associated with the back roll 3 which is coming into contact with the upper endless belt 1 while the slotted wheel ll of the other Geneva mechanism is associated through the cooperating gear wheels 19 and 20 with back roll 4- which is coming into contact with the lower belt 2 and the continuous crimped filament tow 13 is pulled by means of cooperating tension roller-s 1d and 15. The gap between the needle belts 1 and 2 may be changed by back rollers 3 and 4, intermediate rollers 5 and 6 and front rollers 7 and 8 according to the thickness of the filament tow. However, the gap between the belts I and 2 from the back rollers 3 and 4 to intermediate rollers 5 and 6 is made constant, whilst from intermediate rollers 5 and 6 towards front rollers 7 and g the gap is increased gradually by adjusting the rollers 7 and 8 to open the filament tow as it proceeds between the needle belts and to give bulkiness at last.

The tightness of the belt may be adjusted by the control rollers 9 and 10. The intermittent and non-uniform speeds of the belts are produced by the Geneva mechanism-s having a pin wheel and a slotted wheel whereby difference in speed of respective belt and a speed of filament tow due to the tension roller and the difierence in speed of upper and lower belts do not lose the crimped state of the filament and opens the filament tow 13 maintained by needles I6 and 17 of the respective belts. For instance, the circumferential speed of the tension roller is taken as the standard, and the upper and lower belts can make speed change of i8% respectively of the standard and moreover these belts may be alternately moved in such a manner that when the upper belt is running the lower belt remains stationary, thereby giving to the filament tow intermittent and delicate tenseness and slack.

As shown in FIGS. 2 and 3, belts I and 2 are provided with base 18 respectively, to which needles l6 and 17 are fixed by fixing agent 18. If the needle is too thick neps are produced in the filament tow so that it is preferable to use thinner needles and length of about 5 mm. is suitable since if it is too long the needle penetrates too deep into the filament tow to cause breakage of filaments and on the other hand, if it is too short the opening can not be effected sufliciently. The needle is fixed preferably with some inclination in a direction opposite to the advancing direction of belts as shown in FIG. 3. As shown in FIG. 3 the needle with an increased slope in the same direction as the inclination of the needle from about its middle position showed better holding condition of the filament tow and is very convenient to eifect filament opening. On the contrary, too large angle of inclination toward the opposite direction is not desirable because there occurs break down of filaments.

In FIGURES 4 and 5, the Geneva mechanism adopted to operate the upper and lower needle belts intermittently comprises a pin wheel 12 having two pins 21 and 22 and a slotted wheel 11 having slots 24, 25, 26 and 27. Although only one pair of the slotted wheel 11 and the pin wheel 12 are visible in FIGURE 1 owing to overlapping with the back roll 3, two pairs of Geneva mechanisms are arranged symmetrically as shown in FIGURE 5. The back roll 3 is connected coaxially to the slotted wheel 11 and cooperates with upper needle belt I. The lower back roll 4 is also associated through the cooperating gear wheels 19 and 20 with a slotted wheel 11.

In operation, when the pin wheel 12 commences rotation in the direction shown by the arrow, i.e. opposite to the rotational direction of the pin wheel 12, during the time pin wheel 22 is in mesh with the slot 24, the back roll 3 rotates and the rotation of the front roll 3 is converted into the operation of the upper needle belt 1, namely only the upper belt 11 operates. On the other hand, immediately before the pin 22 is disengaged from the slot 24, the pin 22 of the pin wheel 12 of the other Geneva mechanism falls in mesh with the slot 24' of the slotted wheel 11 to rotate said slotted wheel 11, whereby the back roll 4 which is associated through the cooperating gear Wheels 19 and 20 with the slotted wheel 11' commences to rotate. In this instance, only the belt 12 operates and the belt 1 remains stationary. Moreover, immediately before the slotted wheel 11' rotates over an angle of 90 it ceases rotation and the pin 21 of the pin wheel 12 =re-falls in mesh with the slot 25 of the slotted wheel 11. Thus alternate and intermittent operation of the upper and lower belt is etfected repeatedly in accordance with the rotation of the slotted wheel over an angle of 90, thereby imparting the filament tow an intermittent delicate tenseness and slack.

The device of the invention may be made to increase the opening capacity by combining two sets of mechanisms as shown in FIG. 1 according to the condition of filament tow and the purpose.

What I claim is:

1. A device for opening continuous crimped tow to be used for cigarette filters comprising a constant driving means for pulling said crimped tow, two endless belts arranged in a spaced relation to a continuous crimped tow passing between them, each of said belts having needles secured to its surface in definite patterns for acting upon said tow, means for driving said belts intermittently and at unequal relative speeds so that said needles stick into the tow and continuously alternate the tow between a tense and slack condition, and means for gradually increasing the space between said belts in the direction of travel of the tow whereby the tow attains a degree of bulkiness due to the action of said needles.

2. A device as defined in claim 1 wherein said means for driving said belts intermittently and at unequal relative speeds includes two Geneva mechanisms each having a pin wheel and a slotted wheel, said pin wheel having two pins arranged in symmetrically opposite positions to engage in the slots of the slotted wheel so as to provide said slotted wheel with intermittent movement, one of said slotted wheels being associated with the back roll which comes into contact with an upper belt and the other slotted wheel being associated with the other back roll which comes into contact with the lower belt through cooperating gear wheels.

3. A device as defined in claim 2 wherein said needles are inclined in a direction opposite to the direction in which the belt to which they are attached is driven.

FOREIGN PATENTS 302,194 12/1928 Great Britain.

MERVIN STEIN, Primary Examiner.

DORSEY NEWTON, Examiner. 

1. A DEVICE FOR OPENING CONTINUOUS CRIMPED TOW TO BE USED FOR CIGARETTE FILTERS COMPRISING A CONSTANT DRIVING MEANS FOR PULLING SAID CRIMPED TOW,TWO ENDLESS BELTS ARRANGED IN A SPACED RELATION TO A CONTINUOUS CRIMPED TOW PASSING BETWEEN THEM, EACH OF SAID BELTS HAVING NEEDLES SECURED TO ITS SURFACE IN DEFINITE PATTERNS FOR ACTING UPON SAID TOW, MEANS FOR DRIVING SAID BELTS INTERMITTENTLY AND AT UNEQUAL RELATIVE SPEEDS SO THAT SAID NEEDLES STICK INTO THE TOW AND CONTINUOUSLY ALTERNATE THE TOW BETWEEN A TENSE AND SLACK CONDITION, AND MEANS FOR GRADUALLY INCREASING THE SPACE BETWEEN SAID BELTS IN THE DIRECTION OF TRAVEL OF THE TOW WHEREBY THE TOW ATTAINS A DEGREE OF BULKINESS DUE TO THE ACTION O SAID NEEDLES. 